Different metabolic correlations of thrombin-activatable fibrinolysis inhibitor and plasminogen activator inhibitor-1 in non-obese type 2 diabetic patients

We investigated the plasma levels of thrombin-activatable fibrinolysis inhibitor (TAFI), plasminogen activator inhibitor-1 (PAI-1) and their relation with clinical and metabolic parameters in non-obese type 2 diabetic patients. The plasma levels of TAFI and PAI-1 were evaluated in 47 non-obese type 2 diabetic patients and 31 normal subjects. The intra-abdominal visceral and subcutaneous fat areas were measured by computed tomography (CT). The degree of insulin resistance was evaluated by the euglycemic–hyperinsulinemic clamp technique using artificial pancreas. The plasma levels of TAFI (169.0 ± 108.8% versus 103.7 ± 52.3%; p < 0.001, mean ± S.D.) and PAI-1 (82.7 ± 54.5 ng/ml versus 52.9 ± 51.7 ng/ml; p < 0.05) were significantly higher in non-obese type 2 diabetic patients than in normal subjects. Univariate analysis showed that the plasma TAFI levels are significantly and inversely correlated with the glucose infusion rate (GIR) ( r = −0.42, p < 0.005) in all diabetic patients. Moreover, the plasma levels of TAFI were significantly correlated with fasting plasma glucose levels ( r = 0.47, p < 0.001) and HbA 1c ( r = 0.38, p < 0.005) in all subjects. The plasma levels of PAI-1 were significantly and proportionally correlated with the visceral fat area ( r = 0.42, p < 0.005) and body mass index ( r = 0.33, p < 0.05). There was no significant correlation between plasma levels of TAFI and PAI-1 ( r = 0.04). These results show that the plasma levels of TAFI and PAI-1 differently correlate with insulin resistance and visceral fat accumulation, suggesting that different factors are implicated in the plasma elevation of TAFI and PAI-1 in non-obese type 2 diabetes mellitus.